How long does it take to work?

Leflunomide doesn't work immediately. It may take six weeks or more for you notice any benefit and several months before you feel the full effect. Because it's a long-term treatment it's best to keep taking leflunomide (unless you have severe side-effects):

even if it doesn't seem to be working at first

even when your symptoms improve (to help keep your condition under control).

Leflunomide can affect the blood count by reducing the number of blood cells you make, which can make you more likely to pick up infections. It can also affect the liver. You'll have regular blood tests to check for early signs of these side-effects.

What should I do if I experience side-effects?

Tell your doctor or rheumatology nurse straight away if you develop any signs of infection (such as a sore throat or fever) or have unexplained bruising or bleeding, breathlessness, jaundice (yellow skin or eyes) or any other new symptoms that concern you.

You should also see your doctor if you develop chickenpox or shingles or come into contact with someone who has chickenpox or shingles. These illnesses can be severe if you're on leflunomide. You may need antiviral treatment, and your leflunomide may be stopped until you're better.

If you have severe side-effects, your doctor may suggest having a wash-out treatment which will help remove the leflunomide from your body more quickly.

Effects on other treatments

Can I take other medicines alongside leflunomide?

You may be prescribed leflunomide alongside other drugs. Discuss any new medications with your doctor because some drugs interact with leflunomide. Examples include:

warfarin (which thins the blood)

phenytoin (which is used in epilepsy).

Always tell any other doctor treating you that you’re on leflunomide.

You can carry on taking a non-steroidal anti-inflammatory drug (NSAID) or painkillers, if needed, unless your doctor advises otherwise.

Don't take over-the-counter preparations or herbal remedies without discussing this first with your healthcare team.

If you need to start another treatment which could interact with leflunomide, your doctor may suggest having a wash-out treatment to help remove the leflunomide from your body.

Vaccinations

If you're on leflunomide it's recommended that you don't have live vaccines such as yellow fever or shingles. However, sometimes, a live vaccine may be necessary (for example rubella immunisation in women of childbearing age). In this case your doctor will discuss the possible risks and benefits of the immunisation with you.

Pneumococcal vaccine (which gives protection against the most common cause of pneumonia) and yearly flu vaccines are safe and recommended.

Having an operation

If you're going to have an operation, discuss this with your rheumatology team. They may advise you to stop the leflunomide for a time before and after surgery.

Alcohol

Fertility, pregnancy and breastfeeding

If you’re thinking of having a baby, you should discuss your medications with your rheumatology team beforehand.

From the limited evidence available, leflunomide doesn't appear to be harmful in human pregnancy. But because the evidence is so limited, both men and women who are taking leflunomide are advised to use contraception.

Women who want to have a baby are usually advised to stop taking leflunomide and have a special wash-out treatment before trying to become pregnant. If you prefer not to have the wash-out treatment your doctor may advise you to continue using contraception for up to two years after stopping leflunomide.

If you become pregnant while taking leflunomide, stop the drug and speak to your doctor as soon as possible about having the wash-out treatment. As long as you stop the drug and have the wash-out treatment it's very unlikely that leflunomide will have caused any harm to your baby.

As a precaution, men taking leflunomide may also be advised to have the wash-out treatment before trying to father a child.

Breastfeeding isn’t recommended if you’re on leflunomide because it may pass into your breast milk and could affect your baby.

What is a wash-out treatment and why might I need it?

Leflunomide can remain in the body for up to a year after you stop taking it.

In some circumstances it's recommended that leflunomide is eliminated from the body more quickly for example if:

you become pregnant

you have severe side-effects from leflunomide

you need to start another treatment that could interact with leflunomide.

A wash-out treatment will help to remove leflunomide from your body more quickly than usual. This involves taking a drug called cholestyramine for 11 days. You may have blood tests to check that the level of leflunomide in your body is falling.

Who am I and what can I do?

I'm AVA, the Arthritis Virtual Assistant, and I'm being trained by Versus Arthritis to give you general information about your condition and how to manage your symptoms. I can suggest exercises and tell you about medication.

How do I work?

I've been built using artificial intelligence powered by IBM Watson, and I learn and improve through every conversation. Whenever you use me, you're indirectly helping another person get the answers they need.

What can you ask?

I respond best to clear, simple questions about one type of arthritis. For example, "What exercises should I do?" or "How can I help myself?"

What if I want to speak to a real person?

If you need help from a real person here at Versus Arthritis, you can call our free helpline on 0800 5200 520.

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